A new type of video cassette has recently been developed and is gaining in popularity day to day because the video camera is conveniently portable, and the cassette is small and thin, but is capable of recording at length. The cassette is different from the prevailing VHS and BETA cassettes in respect to its size and structure. The biggest difference between the types of cassettes lies in the tape leading post in the front of the cassette. In general, VHS and BETA cassettes both have "rotatable" tape leading posts in the front; when such a cassette is located in a rewinder for rewinding, the tape is not necessarily led out. Instead, direct rewinding of tape can be accomplished through the guidance of two rotatable tape leading posts mounted on the cassette. For the new type of video cassette, the tape leading posts on respective sides in the front are integrally molded together with the cassette so that they are non-rotatable. Before rewinding, therefore, the tape has to be lead out forward so as not to contact non-rotatable tape leading posts to protect the tape from being worn due to fast rewinding. Under such circumstances, even if the prevailing rewinder were changed in design to fit the size and shape of the new type of video cassette, it would still not satisfactorily rewind the video cassette.
Though there are some varieties of rewinder specifically designed for the new type of video cassette, all of their tape leading mechanisms move the two tape leading posts outwardly with motor power and further rely upon a complicated driving and holding mechanism for retaining the led-out tape leading posts temporarily at operating positions. Meanwhile, they have to pull the tape leading mechanism back to the non-operating position with motor power. Therefore, the whole structure is too complicated causing errors and frequent failures.
U.S. patent application Ser. No. 07/832,055, filed on Feb. 6, 1992, discloses an auto rewinder for rewinding the magnetic tape of the new type video cassette. Though it provides effective means to overcome the defects of the prior art, there still are improvements which can be made.